The Biostatistics Core will over see fulfillment of major data collection, data management and data analysis tasks. The Core Director will work closely with investigators and task leaders to pan and complete activities, and will monitor, manage, and report to investigators on activities serving the needs of their projects. The Core Director will oversee the performance of data collection contractors and will coordinate the participation of personnel for data gathering functions not assigned to contractors. Contracted data collection activities include the hypothesis testing formative research of Project 1 and the summative and campaign monitoring surveys of Project 2 conducted in school settings throughout Years 1-5, and the baseline and telephone fellow-up interviews conducted for Projects 3 in Years 1-5. Data collection conducted within projects include pilot studies and process evaluation data for Projects 2 and 3 throughout Years 1-5. The Core Director and staff will provide the interface between data collection activities by contract and project personnel and analysis activities. Core staff will process data received from these sources and will provide quality audits and problem resolution. All data analysis tasks required for these projects will be conducted in the Biostatistics Core. The Core Director and other senior core staff will collaborate closely with investigators on development of reports for publication. The overall functions of the Core throughout the life cycle of the program project can be summarized as: planning, pilot, fielding, post-fielding, analysis, and closeout.